According to the county planning staff report, which recommended approval of the project, the 250,000 square feet of office density represents the last remaining non-residential density available under the proffered maximum 3.465 million square feet of non-residential development approved within Reston’s urban core.

Boston Properties will move the office part of the development to Block 5, where the current FedEx/Kinkos and Ann Taylor are now located, with additional office space above.

The plan calls for turning that three-story retail/office building into a 17-story building with 276,788 square feet of office space and 7,800 square feet of ground-floor retail. The building would also have four levels of underground parking.

The board also approved a reduction in parking of 22 percent (up to 192 fewer spaces) because of its proximity to future mass transit. The planned Reston Parkway Silver Line Metro Station is a half-mile away.